The present invention relates to a display device, and more particularly, to a method of manufacturing a fluorescent layer for a display device.
An image display device which is used for displaying information on a display screen includes a cathode ray tube (CRT) employing the emission of thermal electrons and the light emission of phosphors, a vaccums fluorescent display (VFD) having a principle similar to that of the CRT and whose entire shape is usually flat, a liquid crystal display (LCD) using an electro-optical characteristics of liquid crystals, a plasma display panel (PDP) using a gaseous discharge phenomenon between charged electrodes, and others.
The display devices employ a fluorescent layer of red, green and blue phosphors or a color filter layer for color display.
The fluorescent layer for color display is formed using, for example, a photolithography process or a printing process. However, the photolithography process includes a phosphor composition coating process and exposure, developing and thermal treatment processes which are repeatedly performed, so that it is very long and complicated and, particularly, defects are frequently generated by dust during the exposure and developing processes. Also, before the phosphor composition is coated, an undercoating solution must be coated and thermally treated in order to enhance the adhesion strength of the composition.
Meanwhile, according to the printing method which is usually used in a flat display such as a plasma display panel (PDP) or a field emission display (FED), a uniform phosphor film pattern can be obtained. However, the printing method has the following problems.
First, the thickness of the phosphor pattern formed by this method is inconsistent (the deviation in thickness is about 20%).
Second, since the printing method is based on a screen printing, the resolution is limited to about 80pm so that it is difficult to form a high-resolution phosphor pattern.